The present invention relates to a rib post, for example for use in aerospace structures, for example in an aircraft.
In aircraft, rib posts are used in aerofoils or airfoils (US), such as wings and horizontal/vertical stabilisers to connect internal ribs to spars.
Traditionally, rib posts for use as a primary structure in the construction of aircraft have been in the form of a T-section made from a variety of metallic materials, for example aluminium alloys. An example of a T-section made from metal is illustrated in FIG. 1.
For decades composite materials (also known as composites), for example carbon fibre reinforced composites (composites containing carbon fibres and epoxy resin) have become an increasingly attractive alternative to metal for many aircraft components. The carbon fibre reinforced composite material offers improved properties such as lower weight, improved fatigue/damage resistance, corrosion resistance and negligible thermal expansion.
However, the application of a T-section rib post made from composite materials does not necessarily offer any tangible benefit when compared with its metal counterpart. Design considerations, such as through thickness properties can render a T-section made from composite heavier than the equivalent metal component. Moreover, the complexities of the tooling required to produce a T-section from composite materials may render the composite structure more expensive than an equivalent metal part.